A factor, in data analysis, that causes the effects of two distinct processes to be indistinguishable; a confounding variable(noun)
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Use "confounder" in a sentence
"The confounder is the continually reducing age for obtaining Social Security is supposed to be a way of reducing the total fiscal burden of Social Security by encouraging people to take it earlier for less payout."
"There is always the chance that they might miss some critical confounder that renders their results entirely wrong."
"Unfortunately, the study did not report on levels of physical activity, an important confounder in any study on visceral fat."